Virtual path

ABSTRACT

The present invention pertains to a system and method for specifying links, connectivity and bandwidth in an interconnect fabric. For example, a method for allocating connectivity and bandwidth of an integrated circuit may include receiving an interconnect fabric description, the described interconnect fabric having a plurality of platforms linked over an isochronous interconnect fabric. An arrangement of links of the received interconnect fabric is virtualized based on bandwidth. An arrangement of links of the received interconnect fabric is virtualized based on connectivity. The links are allocated on the basis of the virtualized link arrangements based on bandwidth and connectivity.

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] The present application hereby incorporates the following UnitedStated Patent Applications by reference in their entirety: AttorneyDocket Number Express Mail L.N./U.S.P.N. Filing Date LSI 01-39010/015,194 Nov. 20, 2001 LSI 01-488 10/021,414 Oct. 30, 2001 LSI 01-48910/021,619 Oct. 30, 2001 LSI 01-490 10/021,696 Oct. 30, 2001 LSI 01-524B10/044,781 Jan. 10, 2002 LSI 01-543 10/135,189 Apr. 30, 2002 LSI 01-69509/842,335 Apr. 25, 2001 LSI 01-827 10/034,839 Dec. 27, 2001 LSI 01-828B10/061,660 Feb. 1, 2002 LSI 02-0166 10/135,869 Apr. 30, 2002 LSI 02-0560EV 087 433 682 US Jun. 27, 2002 LSI 02-4372 EV 087 433 696 US Jun. 27,2002 LSI 02-0383 EV 087 433 461 US Jul. 31, 2002 LSI 02-4466 EV 087 433461 US Jul. 31, 2002

FIELD OF THE INVENTION

[0002] The present invention generally relates to the field ofintegrated circuit design, and particularly to virtualization ofintegrated circuit resources for resource allocation and optimization.

BACKGROUND OF THE INVENTION

[0003] Integrated circuits (IC) have become an important aspect in anever increasing array of devices. From network storage systems towireless phones, integrated circuits are relied upon to provide thefunctionality desired by this wide range of devices. To meet this rangeof uses, the integrated circuit may be designed specifically to meet acontemplated need, as well as designed to provide functionality desiredin a wide range of instances. The types and functionality desired inintegrated circuits is almost limitless.

[0004] Thus, integrated circuits have become a necessary part of adiverse range of everyday modern society. To provide this functionality,integrated circuits may need to be specialized to have the functionsnecessary to achieve the desired results, such as through the provisionof an application specific integrated circuit (ASIC). An ASIC istypically optimized for a given function set, thereby enabling thecircuit to perform the functions in an optimized manner. However, theremay be a wide variety of end-users desiring such targeted functionality,with each user desiring different functionality for different uses.

[0005] Additionally, more and more functions are being included withineach integrated circuit. While providing a semiconductor device thatincludes a greater range of functions supported by the device, inclusionof this range further complicates the design and increases thecomplexity of the manufacturing process. Further, such targetedfunctionality may render the device suitable for a narrow range ofconsumers, thereby at least partially removing an “economy of scale”effect that may be realized by selling greater quantities of the device.

[0006] Therefore, there is a need for a system and method that mayoptimize both specialized and general purpose integrated circuits thatwill address the increased functional count and diverse functionality ofthe integrated circuits that may be encountered.

SUMMARY OF THE INVENTION

[0007] Accordingly, the present invention is directed to a system andmethod for virtualizing links in an interconnect fabric having aplurality of platforms. In a first aspect of the present invention, asystem comprises a plurality of platforms communicatively coupledutilizing an interconnect fabric and a program of instructions suitablefor being performed by the plurality of platforms. The program ofinstructions configures the plurality of platforms to aggregatebandwidth between platforms.

[0008] In an additional aspect of the present invention, a method forallocating connectivity and bandwidth of an integrated circuit includesreceiving an interconnect fabric description, the described interconnectfabric having a plurality of platforms linked over an isochronousinterconnect fabric. An arrangement of links of the receivedinterconnect fabric is virtualized based on bandwidth. An arrangement oflinks of the received interconnect fabric is virtualized based onconnectivity. The links are allocated on the basis of the virtualizedlink arrangements based on bandwidth and connectivity so thatconnectivity of the fabric is distributed independently of the bandwidthof the fabric.

[0009] In a further aspect of the present invention, a method forallocating connectivity and bandwidth of an integrated circuit includesreceiving an interconnect fabric description, the described interconnectfabric having a plurality of platforms linked over an isochronousinterconnect fabric. An arrangement of links of the receivedinterconnect fabric is virtualized based on bandwidth. An arrangement oflinks of the received interconnect fabric is virtualized based onconnectivity. The links are allocated on the basic of the virtualizedlink arrangements based on bandwidth and connectivity.

[0010] It is to be understood that both the forgoing general descriptionand the following detailed description are exemplary and explanatoryonly and are not restrictive of the invention as claimed. Theaccompanying drawings, which are incorporated in and constitute a partof the specification, illustrate an embodiment of the invention andtogether with the general description, serve to explain the principlesof the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The numerous advantages of the present invention may be betterunderstood by those skilled in the art by reference to the accompanyingfigures in which:

[0012]FIG. 1 is a block diagram of an exemplary embodiment of thepresent invention wherein an arrangement of platforms in a taurus isshown;

[0013]FIG. 2 is a diagram of an exemplary embodiment of the presentinvention wherein a plurality of platforms are shown, the platforms inan interconnect fabric; and

[0014]FIG. 3 is a flow diagram depicting an exemplary method of thepresent invention.

DETAILED DESCRIPTION OF THE INVENTION

[0015] Reference will now be made in detail to the presently preferredembodiments of the invention, examples of which are illustrated in theaccompanying drawings.

[0016] Referring generally now to FIGS. 1 through 3, exemplaryembodiments of the present invention are shown. One way of organizing achip internally with respect to both internal and external resources isto incorporate the components into what may be called a switchingfabric, where resources might exist at what are referred to as “nodes”within the device. The nodes may be connected by a set of links, i.e.the wires between the nodes, and these, in turn, form a regularstructure, which is called a fabric, which may be connected in loops orthe like. For instance, a fabric may be formed having a two-dimensionalstructure which is looped around at the ends, that logically forms ataurus, an example of which is shown in FIG. 1.

[0017] Another fabric has been described in copending application Ser.No. 10/044,781, filed Jan. 10, 2002, which was incorporated by referencein its entirety. In particular, the application describes a “Sea ofPlatforms”, and in an embodiment described, each node is a platformcomprising a processor, an FPGA block and memory block, a reconfigurablecore and the like, in a regular pattern.

[0018] The present invention addresses a variety of aspects, andspecifically three aspects, of the characteristics of the fabric itself,and in particular, the allocation of resources within the switchingfabric. In one embodiment, it may be assumed that at each node in aswitching fabric, a switch is provided which operates to direct trafficwithin the switching fabric. The switch may be separate and apart fromthe platform that also exists at the node. Traffic into and out of thenode may be controlled by the behavior of the switch.

[0019] The allocation problem has to do with how scarce resources withinthe chip and, more particularly, within the fabric are allocated betweenthe links and nodes, and the bandwidth that is required. For instance,for a particular function that is implemented using a chip that isorganized in the form of a switching fabric, it may be determined that,for functional reasons, one particular node had a requirement that it beparticularly richly connected to a large number of other nodes becauseof the function that the node is fulfilling. For example, a particularnode could be required to have simultaneous connectivity that went quitefar afield in the chip.

[0020] Therefore, in some instances, the surrounding nodes may need toknow whether the node is a pass-through node, or not. The traffic in thefabric, for instance, may not be limited to physically contiguous nodes,but rather may logically implicate far-reaching nodes in many cases.Thus, there is a problem of how the links and the nodes are allocated.

[0021] In further cases, situations may also be encountered where thebandwidth should be allocated as well. For example, as shown in theembodiment 200 depicted in FIG. 2, a case may be encountered in which afirst node 202 and a second node 204 are closely connected forfunctional reasons but have limited bandwidth between each other, whilea node 206 further apart in the fabric may require greater bandwidthwith the first node 202. Thus, the three allocation problems of how tooptimally allocate links and nodes and bandwidth form a key problem inthe design and specification of switching fabrics. Through use of thepresent invention, the resources of the chip may be “virtualized” in asense for optimization of the circuit design.

[0022] For instance, as shown in FIG. 2, each link between nodes in aswitching fabric may actually have four physical wires capable ofsustaining some particular bandwidth, so the peak bandwidth that ispossible to construct between any two nodes would be four-in. Thus, in afirst instance, it may be required that the bandwidth between two nodesbe two-in; that is, twice the maximum bandwidth that one wire is capableof supporting.

[0023] There may be a large number of ways to provide the desiredbandwidth. By virtualizing the allocation problem, a number of differentsolutions may be examined. For example, by obtaining two-in bandwidth,but not necessarily having the same pair of wires in parallel going toeach node, such as by utilizing isochronous switching that connects thenodes. In other words, by having regularly-timed, regularly-clockedtransitions on all of the physical wires in the fabric at once, solutionflexibility is provided.

[0024] One reason that this solution is attractive is that it offers anadditional degree of freedom in allocating the links in the switchingfabric with respect to how the links contribute to satisfying thebandwidth requirements between any two nodes.

[0025] Another interesting aspect of the virtualization of the presentinvention is that the bandwidth requirements between the nodes may varywith time, so that, in effect, the allocation in a previous instance maybe discarded and reallocated to a different set of links in a secondepisode. This may be, in turn, a function of all of the other trafficthat is present on the fabric at that particular instant of time.

[0026] Being able to dismantle the actual wires between nodes in the waypreviously described so that the individual wires may be allocated tomanaging traffic in a particular way is attractive in the sense that itoffers additional degrees of freedom.

[0027] In some encountered embodiments, this may require additionaloverhead because there may be additional circuitry that is required ineach switch and/or in each node, which will decide which transmissionprocess that particular physical wire is implicated in at thatparticular time. However, this may be a function of the isochronousprotocol devised to manage the traffic on the individual physical links,which is set up and affiliated with one another. Thus, the protocol maybecome an integral means of implementing a scheme of this kind.

[0028] The present invention addresses the problem of bandwidthallocation by completely virtualizing the allocation of links.Therefore, the present invention provides the functionality ofmanagement of the switching fabric on the device, including associatingnodes with one another. Preferable, the present invention may satisfynode bandwidth requirements by literally any set of paths connectingindividual wires, and include distant paths to “remote” portions of thechip. For instance, the links may be virtualized in such a manner as tobe mathematically described so that routes may be chosen in the chiputilizing any of a number of desired algorithms. With a suitably-chosenprotocol, through use of the present invention, an isochronous fabric iscapable of sustaining that set of discrepant leaps over the links in thefabric.

[0029] For example, referring now to FIG. 3, an exemplary method 300 ofthe present invention is shown wherein an allocation of resources in afabric is performed based on bandwidth and connectivity. An interconnectfabric description having a plurality of links and nodes is received302. An arrangement of links of the received interconnect fabric isvirtualized based on bandwidth 304 and is also vitualized based onconnectivity 306. The links of the fabric and then allocated based onthe virtualized arrangements of connectivity and bandwidth 308. In thisway, a designer may take this discrepant mapping as virtualized andbring it back into co-incidence so that optimal allocations may be made.

[0030] In particular, the present invention provides deterministiccontrol over the number of clock cycles required to provide simultaneousarrival of all the constituent elements in a piece of data beingtransmitted over the bandwidth utilizing an isochronous signal with asuitable isochronous protocol managing the whole thing. For example,suppose a designer is concerned with bandwidth and traffic between twoparticular nodes. From a formal, purely abstract point of view, such asa mathematical point of view, the set of all possible individual wiresconnecting to a group may be viewed in a sort of “traveling salesman”problem. Thus, the query may be, of that set of all possible singlewires following all possible sets of paths, which wires are available toin light of the currently prevailing traffic model that is beingsupported by the switching fabric at a particular instant in time.Current methodology and protocols do not permit that virtualization ofthe physical links to that degree, and effectively, it is not possiblein the absence of the present invention.

[0031] In effect, this puts a constraint on the “traveling salesman”problem and makes it more manageable. There are further constraints thatmay be imposed on this problem in order to make it calculable withpolynomial time algorithms.

[0032] The present invention offers flexibility of aggregation of linksso that the bandwidth between nodes may be greater than otherwisepossible. For instance, the present invention may take advantage of aset of wires, such as the four wires shown between each node in FIG. 2.Through use of the present invention, the wires located between eachnode need not be implicated and devoted to traffic between neighboringnodes, but rather may be allocated to distant nodes. For example, ratherthan being devoted to traffic between a first and second neighboringnode, the wires may be allocated between remote nodes. Such allocationmay be provided through algorithmic and/or deterministic data thatindicates the usage of the wires in the path. For instance, it may bedetermined that wires in a path, at a particular point in time, are notinvolved in traffic between neighboring nodes. Therefore, the wires arefree to be allocated to satisfy other resource requires of the fabric.

[0033] It should be noted that this aspect of the present inventionprovides the capability of assembling paths that have greater bandwidththan four physical wires are capable of supporting in the presentexample. In other words, sets of wires may be aggregated between pairsof nodes that would support greater bandwidth. Thus, bandwidth may bescaled beyond the physical limitations of the particular physical linksin the fabric.

[0034] This may have the effect in certain embodiments of a fabric, ofreducing the ability of the fabric to support richness and connectivity.Therefore, there may be a continuous trade-off between richness andconnectedness and the ability to support peak aggregate bandwidth, whichmay be addressed as desired by the present invention. In this way, thepresent invention provides increased flexibility by allowing a designerto optimize the structure based on these considerations.

[0035] Additionally, an upper bound may be imposed, such as a threshold,on the ability of the fabric to aggregate links in satisfaction ofbandwidth requirements to ensure that the problem is solvable in anefficient manner utilizing the resources of the fabric.

[0036] Another important area is the question of imposing upper boundson the amount of aggregation that is supported in any particular fabric.In other words, the upper bound on the amount of aggregation that ispermitted may be closely tied to the upper bound or the dimensionalityof the fabric. For instance, referring back to the two-dimensionaltaurus of FIG. 1, even hyper-tauri that have four, five, six and moredimensions may be supported by the fabric. With higher-dimensionalspaces, the aggregation possibilities are greater because the richnessof the connectivity is greater. The higher-dimensional connectivitypossibilities will become more important in mapping and controllinghigh-complexity devices as component count increases. In other words,where instead of hundreds of thousands and millions of gates areencountered; a designer in the near future may have billions of gates.Thus, the present invention provides a way of beginning the next plateauin attacking the problem of scaling billion-gate designs. In this way,the present invention may provide higher bandwidths through aggregationthan would otherwise be supported between nodes of the fabric

[0037] The present invention also provides for decomposition of the linkstructure in satisfaction of bandwidth allocation in support of theother problem encountered by designers, which has to do with how nodesand bandwidth are treated. A fabric may have connectivity in the nodethat follows a power-law distribution.

[0038] For example, one of the things determined about these networksthrough investigation of the present invention, can be summarized in asimple way, in that, in large, complex networks, like the Internet, aswell as in much simpler networks, it is often the case that a smallnumber of nodes account for most of the connectivity. In other words,most of the connections are made to a small number of nodes, and followa power-law decay, while the vast bulk of nodes have, correspondingly,relatively few connections and links to them. That is opposed to aGaussian distribution, which, in many cases, previously had been assumedto be the case for how node connectivity is distributed in networks.

[0039] This has an important implication to the design of chips, becauseto govern a chip that is employing a switching fabric, situations may beencountered in which a few of the nodes handle the vast amount ofconnectivity. While it should be realized that there may be instances inwhich this is not encountered, through use of the present invention, thesituations may be determined and addressed to improve the efficiency andperformance of the fabric and chip.

[0040] Connectivity is only one aspect of the sort of differentialdensity that the chip is encountering. The other aspect is the bandwidthrequirement, and notice that the bandwidth requirement is completelyindependent of the physical connectivity, per se. In other words, afirst node and a second node may have explicit connectivity to most ofthe other nodes in the network, but that does not necessarily imply thatthe bandwidth that is supported by the nodes is also equivalentlydistributed with the connectivity.

[0041] Thus, if instead of being perfectly matched so that connectivityand the bandwidth correspond to the same set of nodes, bandwidth andconnectivity may be configured to be discrepant. Therefore, inimplementation, connectivity may observe a power-law distribution withrespect to one set of nodes, but bandwidth may observe a power-lawdistribution with respect to a different set of nodes. Thedisaggregation of links, i.e. the ability to allocate links at willbetween sets of nodes, allows a designer to take this discrepant mappingand bring it back into co-incidence so that optimal allocations may bemade, according to a virtualized connectivity and bandwidth rule. Thishas the effect of maximizing the use of the resources in the device.Bandwidth allocation, which in some instances is extremely skewed, thatis, it is asymmetrical with respect to the number of nodes that itinvolves, and connectivity, which may follow, arguably, a power-lawdistribution, even though it is not the same set of nodes that isinvolved, by virtualizing the links, in the way as previously described,so that the links themselves may be allocated accordingly. Thus, thepresent invention may address those two sets of distributions and drawthem into co-incidence.

[0042] For example, referring now to FIG. 3, an exemplary method of thepresent invention is shown wherein virtualization of links in aswitching fabric is utilized to optimize fabric functionality throughboth bandwidth allocation and connectivity.

[0043] The present invention provides a set of algorithmic proceduresfor measuring the distributions, the independent distributions ofconnectivity of links and bandwidths within a switching fabric and thenreallocating disaggregated link structures independently so as to bringthose two distributions into conjunction with one another. In this way,an optimal allocation of resources is provided, such as the physicalresources within the switch based on a switching fabric.

[0044] There are a variety of ways of determining which nodes are thehigh traffic nodes. For example, one is by sampling, in which, usage isto be measured and detected and the high-traffic nodes inferred from theactual behavior. Another technique is that the determination may beperformed parametrically by design. In actual use, both methods may beutilized. Optimization may be superior to the extent that bothtechniques are used; that is, by design, a designer may specifyparametrically, estimates of bandwidth allocation and then measure thedegree of which actual usage pattern deviates.

[0045] Additionally, the allocation that was described earlier, in whichthe individual link wires were disaggregated, e.g. the physical entitiesthat connect nodes together, that algorithm may actually be applieddynamically and may be used to assign bandwidth on a dynamic basis asconditions vary within a switching fabric. Even though some changes maybe made in what was previously considered a “dynamic” way, those changeswere actually performed in a rigid, fixed sort of way, and lacked thedegrees of freedom for reallocating bandwidth within a chip of thepresent invention.

[0046] One of the motivations for the present invention is that inlooking at the switching structures, the organization of switchingfabrics and the behavior of switching elements within traditionalswitching fabrics (which come out of completely different disciplinesthan a person of ordinary skill in the art would encounter in chipdesign), it was discovered that the kinds of traffic models that adesigner was apt to encounter in high-complexity devices are quitedifferent than the canonical traffic models that are encountered inother disciplines. For example, Telco switching, Internet switching,video switching, storage-area networks, wide-area networks, ATMswitching, local-area networks (LANs), and the like, which are thetraditional sources of models for switching fabrics may not support thecomplex device the designer encountered in an optimal manner in mostinstances.

[0047] In order for this kind of approach to be truly effective indesigning large-scale devices, with up to billions of components, thisadditional functionality is needed. It clearly applies in the case inwhich control the physical instantiation of the fabric is possible, dueto the designer actually making the device and proceeding tofabrication. In other words, as opposed to the more general case, wherea designer has to build for every contingency.

[0048] For example, once a designer has laid the infrastructure inplace, it is fixed with respect to function and with respect toconnectivity. The structure typically cannot be reallocated on the fly.However, when a designer is building the chip itself, every time a newchip is designed, a new fabric and infrastructure is provided. Thus, adesigner has the luxury of being able to completely revisit a set ofallocation optimizations and do the allocations differently in supportof a different design.

[0049] In this way, the disaggregation of the links permits a designerto take isomorphic but discrepant allocations of connectivity andbandwidth and bring them into conjunction through reassessment of thelink structures, and that is an elegant and powerful resolution of theoptimization problem within these complex devices.

[0050] Thus, the present invention more fully addresses the problem thanprevious FPGA problem of mapping, which was specifically directed at theappropriate way of hooking up CLDs and resources on a FPGA. What waspreviously addressed was the purely structural aspect of it, as opposedto the present invention in which a designer may take a link set andabstract it completely and then use it as a basis for bringing thestructure and the bandwidth into co-incidence. Typically, FPGAarchitectures are not concerned with that problem, and thus tend toapproach it differently.

[0051] A variety of constraints may be provided to create a polynomialtime solution to a particular routing problem as will be apparent to aperson of ordinary skill in the art.

[0052] In exemplary embodiments, the methods disclosed may beimplemented as sets of instructions or software readable by a device.Further, it is understood that the specific order or hierarchy of stepsin the methods disclosed are examples of exemplary approaches. Basedupon design preferences, it is understood that the specific order orhierarchy of steps in the method can be rearranged while remainingwithin the scope of the present invention. The accompanying methodclaims present elements of the various steps in a sample order, and arenot meant to be limited to the specific order or hierarchy presented.

[0053] Although the invention has been described with a certain degreeof particularity, it should be recognized that elements thereof may bealtered by persons skilled in the art without departing from the spiritand scope of the invention. One of the embodiments of the invention canbe implemented as sets of instructions resident in the memory of one ormore information handling systems, which may include memory for storinga program of instructions and a processor for performing the program ofinstruction, wherein the program of instructions configures theprocessor and information handling system. Until required by theinformation handling system, the set of instructions may be stored inanother readable memory device, for example in a hard disk drive or in aremovable medium such as an optical disc for utilization in a CD-ROMdrive and/or digital video disc (DVD) drive, a compact disc such as acompact disc-rewriteable (CD-RW), compact disc-recordable and erasable;a floppy disk for utilization in a floppy disk drive; a floppy/opticaldisc for utilization in a floppy/optical drive; a memory card such as amemory stick, personal computer memory card for utilization in apersonal computer card slot, and the like. Further, the set ofinstructions can be stored in the memory of an information handlingsystem and transmitted over a local area network or a wide area network,such as the Internet, when desired by the user.

[0054] Additionally, the instructions may be transmitted over a networkin the form of an applet that is interpreted or compiled aftertransmission to the computer system rather than prior to transmission.One skilled in the art would appreciate that the physical storage of thesets of instructions or applets physically changes the medium upon whichit is stored electrically, magnetically, chemically, physically,optically or holographically so that the medium carries computerreadable information.

[0055] It is believed that the system and method of the presentinvention and many of its attendant advantages will be understood by theforgoing description. It is also believed that it will be apparent thatvarious changes may be made in the form, construction and arrangement ofthe components thereof without departing from the scope and spirit ofthe invention or without sacrificing all of its material advantages. Theform herein before described being merely an explanatory embodimentthereof. It is the intention of the following claims to encompass andinclude such changes.

What is claimed is:
 1. A system, comprising: a plurality of platformscommunicatively coupled utilizing an interconnect fabric; and a programof instructions suitable for being performed by the plurality ofplatforms, wherein the program of instructions configures the pluralityof platforms to aggregate bandwidth between platforms.
 2. The system asdescribed in claim 1, further comprising allocating bandwidth between afirst platform and a second platform of the plurality of platforms thatincludes bandwidth that otherwise would not have been utilized by athird platform.
 3. The system as described in claim 2, wherein thebandwidth is allocated on the basis of a virtualized arrangement oflinks based on bandwidth and a virtualized arrangement of links based onconnectivity.
 4. The system as described in claim 2, further comprisingreallocating bandwidth at a second episode in time in a manner which isdifferent from a previous allocation of bandwidth in the plurality ofplatforms at a first episode in time.
 5. The system as described inclaim 1, wherein a substantial portion of the plurality of platformsinclude switches which operate to direct traffic within the fabricinterconnect.
 6. The system as described in claim 5, wherein theswitches of the substantial portion of the plurality of platforms areseparate and apart from the respective platforms.
 7. The system asdescribed in claim 1, wherein the program of instructions includes aprotocol which determines a transmission process that a particularphysical wire of the interconnect fabric is implicated in at aparticular episode of time.
 8. The system as described in claim 1,wherein the fabric is isochronous.
 9. The system as described in claim1, wherein a first set of platforms of the plurality of platforms followa power-law distribution with respect to connectivity and a second setof platforms of the plurality of platforms follow a power-lawdistribution with respect to bandwidth, the first set of platforms beingdifferent than the second set of platforms.
 10. A method for allocatingconnectivity and bandwidth of an integrated circuit, comprising:receiving an interconnect fabric description, the described interconnectfabric having a plurality of platforms linked over an isochronousinterconnect fabric; virtualizing an arrangement of links of thereceived interconnect fabric based on bandwidth; virtualizing anarrangement of links of the received interconnect fabric based onconnectivity; and allocating the links based on the virtualized linkarrangements based on bandwidth and connectivity so that connectivity ofthe fabric is distributed independently of the bandwidth of the fabric.11. The method as described in claim 10, wherein the links are allocatedso that the plurality of platforms aggregate bandwidth between at leasta portion of the platforms.
 12. The method as described in claim 10,wherein bandwidth is allocated between a first platform and a secondplatform of the plurality of platforms that includes bandwidth thatotherwise would not have been utilized by a third platform.
 13. Themethod as described in claim 10, further comprising reallocatingbandwidth at a second episode in time in a manner which is differentfrom a previous allocation of bandwidth in the plurality of platforms ata first episode in time.
 14. The method as described in claim 10,wherein a substantial portion of the plurality of platforms includeswitches which operate to direct traffic within the fabric interconnect.15. The method as described in claim 14, wherein the switches of thesubstantial portion of the plurality of platforms are separate and apartfrom the respective platforms.
 16. The method as described in claim 10,wherein the program of instructions includes a protocol which determinesa transmission process that a particular physical wire of theinterconnect fabric is implicated in at a particular episode of time.17. The method as described in claim 10, wherein the fabric isisochronous.
 18. The method as described in claim 10, wherein a firstset of platforms of the plurality of platforms follow a power-lawdistribution with respect to connectivity and a second set of platformsof the plurality of platforms follow a power-law distribution withrespect to bandwidth, the first set of platforms being different thanthe second set of platforms.
 19. A method, comprising: receiving aninterconnect fabric description, the described interconnect fabrichaving a plurality of platforms linked over an isochronous interconnectfabric; virtualizing an arrangement of links of the receivedinterconnect fabric based on bandwidth; virtualizing an arrangement oflinks of the received interconnect fabric based on connectivity; andallocating the links based on the virtualized link arrangements based onbandwidth and connectivity.
 20. The method as described in claim 19,wherein bandwidth is allocated between a first platform and a secondplatform of the plurality of platforms that includes bandwidth thatotherwise would not have been utilized by a third platform.
 21. Themethod as described in claim 19, wherein the links are allocated so thatthe plurality of platforms aggregate bandwidth between at least aportion of the platforms.
 22. The method as described in claim 19,further comprising reallocating bandwidth at a second episode in time ina manner which is different from a previous allocation of bandwidth inthe plurality of platforms at a first episode in time.
 23. The method asdescribed in claim 19, wherein a substantial portion of the plurality ofplatforms include switches which operate to direct traffic within thefabric interconnect.
 24. The method as described in claim 23, whereinthe switches of the substantial portion of the plurality of platformsare separate and apart from the respective platforms.
 25. The method asdescribed in claim 19, wherein the program of instructions includes aprotocol which determines a transmission process that a particularphysical wire of the interconnect fabric is implicated in at aparticular episode of time.
 26. The method as described in claim 19,wherein the fabric is isochronous.
 27. The method as described in claim19, wherein a first set of platforms of the plurality of platformsfollow a power-law distribution with respect to connectivity and asecond set of platforms of the plurality of platforms follow a power-lawdistribution with respect to bandwidth, the first set of platforms beingdifferent than the second set of platforms.